SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c4c4f9dfb694dba6faaaae3d9ff2b60a8ae7eab4002a59c9727c636c12d70d64' 
  AND token = 'D47hWdnkcfRWJ2yAe/+eqdPHO3SCblsv4YlHy2myWo4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}